Various methods of constructing luminaires and housing for luminaires are known. One common method is to form walls from various panels that are connected by screws or other fasteners. These assemblies typically result in light leaks at the corners of the assembly.
U.S. Pat. No. 3,235,989 to Brooks discloses the general concept of a frame for an illuminated sign where the frame is formed from four panels connected together by L-shaped brackets. The brackets are attached to the frame panels by screws and bolts.
U.S. Pat. No. 3,863,372 to Stilling discloses a sign box where the frame is assembled from panels and L-shaped gusset members. The gusset members have two legs with a plurality of teeth for engaging a recess in the side panels to secure the panels together.
U.S. Pat. No. 4,267,657 to Kloke discloses an illuminated sign where the side panels of the frame are assembled using an L-shaped corner piece. The corner piece includes legs having a plurality of teeth to engage the inner surfaces of the corner panels.
U.S. Pat. No. 4,449,166 to Sharp discloses a lighting fixture and air flow support system including a surrounding frame for forming an air supply. The frame includes side panels that are connected together by an L-shaped corner piece. The corner piece is received in the open ends of the respective panels and secured by screws passing through the walls of the side panels.
U.S. Pat. No. 4,630,386 to Wilson discloses a reversible picture frame where the frame is constructed from side panels connected together by an L-shaped corner member having teeth for engaging the surfaces of the frame.
U.S. Pat. No. 4,851,971 to MacLagan discloses a transparency illuminator having a frame formed from four panels where the panels are connected together by L-shaped corner members 86 as shown in FIG. 4.
U.S. Pat. No. 6,592,237 to Pledger discloses a panel frame for providing ventilation to a lighting fixture. The panel frame as shown in FIG. 8 includes four panels coupled together by lugs 40 extending from one end of each of the panels. The lugs engage dimples 50 to connect the panels together.
WO 95/30979 discloses an illuminated display sign having an outer frame formed from panels coupled together by an L-shaped bracket.
JP 54-115574 discloses a housing formed from extruded panels that are coupled together by L-shaped clip members 9. The panels include grooves that engage the coupling member 6.
JP 2009-123545 discloses a picture frame having a lighting device inside the frame. The frame includes four extruded panels coupled together by an L-shaped corner member.
DE 32 43 8883 discloses a corner connection for a lighting fixture. The lighting fixture includes corner members for connecting a plurality of panels together for assembling a plurality of lighting fixtures together.
While various prior assemblies are generally suitable for their intended use, there is a continuing need for improved lighting assemblies and luminaires.